This invention relates to spread spectrum communications and more particularly to a personal communications network which communicates over the same spectrum as used by a plurality of existing narrowband microwave users.
The current fixed service, microwave system uses the frequency band 1.85-1.99 GHz. Microwave users in this frequency band typically have a bandwidth of 10 MHz or less.
A problem in the prior art is the limited capacity of the channel, due to the number of channels available in the fixed service, microwave system.
A base station is in a spread spectrum code division multiple access (CDMA) communication system which co-exists with a microwave system. The microwave system selectively utilizes various microwave frequencies within a selected range of frequencies. The base station generates a plurality of spread spectrum CDMA data signals using pseudo random chip code sequences. The spread data signals encompass the selected range. The base station notch filters the spread data signals at microwave frequencies within the selected range used by the microwave system. The notch filtered spread data signals are transmitted to personal communication network units.